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arXiv · 2012.08638

High-Power Near-Concentric Fabry-Perot Cavity for Phase Contrast Electron Microscopy

Carter Turnbaugh·Jeremy J. Axelrod·Sara L. Campbell·Jeske Y. Dioquino·Petar N. Petrov·Jonathan Remis·Osip Schwartz·Zanlin Yu·Yifan Cheng·Robert M. Glaeser·Holger Mueller
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Abstract

Transmission electron microscopy (TEM) of vitrified biological macromolecules (cryo-EM) is limited by the weak phase contrast signal that is available from such samples. Using a phase plate would thus substantially improve the signal-to-noise ratio. We have previously demonstrated the use of a high-power Fabry-Perot cavity as a phase plate for TEM. We now report improvements to our laser cavity that allow us to achieve record continuous-wave intensities of over 450 GW/cm$^{2}$, sufficient to produce the optimal 90° phase shift for 300 keV electrons. In addition, we have performed the first cryo-EM reconstruction using a laser phase plate, demonstrating that the stability of this laser phase plate is sufficient for use during standard cryo-EM data collection.

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Carter Turnbaugh, Jeremy J. Axelrod, Sara L. Campbell, Jeske Y. Dioquino, Petar N. Petrov, Jonathan Remis, Osip Schwartz, Zanlin Yu, Yifan Cheng, Robert M. Glaeser, Holger Mueller. 2020-12-14. High-Power Near-Concentric Fabry-Perot Cavity for Phase Contrast Electron Microscopy. https://doi.org/10.1063/5.0045496

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